1   /**
2    * Copyright (c) 2000-2009 Liferay, Inc. All rights reserved.
3    *
4    *
5    *
6    *
7    * The contents of this file are subject to the terms of the Liferay Enterprise
8    * Subscription License ("License"). You may not use this file except in
9    * compliance with the License. You can obtain a copy of the License by
10   * contacting Liferay, Inc. See the License for the specific language governing
11   * permissions and limitations under the License, including but not limited to
12   * distribution rights of the Software.
13   *
14   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20   * SOFTWARE.
21   */
22  
23  package com.liferay.portal.kernel.messaging;
24  
25  import com.liferay.portal.kernel.log.Log;
26  import com.liferay.portal.kernel.log.LogFactoryUtil;
27  import com.liferay.portal.kernel.util.ConcurrentHashSet;
28  
29  import java.util.Collection;
30  import java.util.HashMap;
31  import java.util.Map;
32  import java.util.Set;
33  
34  /**
35   * <a href="DefaultMessageBus.java.html"><b><i>View Source</i></b></a>
36   *
37   * @author Michael C. Han
38   */
39  public class DefaultMessageBus implements MessageBus {
40  
41      public synchronized void addDestination(Destination destination) {
42          _destinations.put(destination.getName(), destination);
43  
44          fireDestinationAddedEvent(destination);
45      }
46  
47      public void addDestinationEventListener(
48          DestinationEventListener destinationEventListener) {
49  
50          _destinationEventListeners.add(destinationEventListener);
51      }
52  
53      public void addDestinationEventListener(
54          String destinationName,
55          DestinationEventListener destinationEventListener) {
56  
57          Destination destination = _destinations.get(destinationName);
58  
59          if (destination != null) {
60              destination.addDestinationEventListener(destinationEventListener);
61          }
62      }
63  
64      public void destroy() {
65          shutdown(true);
66      }
67  
68      public int getDestinationCount() {
69          return _destinations.size();
70      }
71  
72      public Collection<String> getDestinationNames() {
73          return _destinations.keySet();
74      }
75  
76      public Collection<Destination> getDestinations() {
77          return _destinations.values();
78      }
79  
80      public boolean hasDestination(String destinationName) {
81          return _destinations.containsKey(destinationName);
82      }
83  
84      public boolean hasMessageListener(String destinationName) {
85          Destination destination = _destinations.get(destinationName);
86  
87          if ((destination != null) && destination.isRegistered()) {
88              return true;
89          }
90          else {
91              return false;
92          }
93      }
94  
95      public synchronized boolean registerMessageListener(
96          String destinationName, MessageListener messageListener) {
97  
98          Destination destination = _destinations.get(destinationName);
99  
100         if (destination == null) {
101             throw new IllegalStateException(
102                 "Destination " + destinationName + " is not configured");
103         }
104 
105         boolean registered = destination.register(messageListener);
106 
107         if (registered) {
108             fireMessageListenerRegisteredEvent(destination, messageListener);
109         }
110 
111         return registered;
112     }
113 
114     public synchronized Destination removeDestination(String destinationName) {
115         Destination destinationModel = _destinations.remove(destinationName);
116 
117         destinationModel.removeDestinationEventListeners();
118         destinationModel.unregisterMessageListeners();
119 
120         fireDestinationRemovedEvent(destinationModel);
121 
122         return destinationModel;
123     }
124 
125     public void removeDestinationEventListener(
126         DestinationEventListener destinationEventListener) {
127 
128         _destinationEventListeners.remove(destinationEventListener);
129     }
130 
131     public void removeDestinationEventListener(
132         String destinationName,
133         DestinationEventListener destinationEventListener) {
134 
135         Destination destination = _destinations.get(destinationName);
136 
137         if (destination != null) {
138             destination.removeDestinationEventListener(
139                 destinationEventListener);
140         }
141     }
142 
143     public void replace(Destination destination) {
144         Destination oldDestination = _destinations.get(destination.getName());
145 
146         oldDestination.copyDestinationEventListeners(destination);
147         oldDestination.copyMessageListeners(destination);
148 
149         removeDestination(oldDestination.getName());
150 
151         addDestination(destination);
152     }
153 
154     public void sendMessage(String destinationName, Message message) {
155         Destination destination = _destinations.get(destinationName);
156 
157         if (destination == null) {
158             if (_log.isWarnEnabled()) {
159                 _log.warn(
160                     "Destination " + destinationName + " is not configured");
161             }
162 
163             return;
164         }
165 
166         message.setDestinationName(destinationName);
167 
168         destination.send(message);
169     }
170 
171     public void shutdown() {
172         shutdown(false);
173     }
174 
175     public synchronized void shutdown(boolean force) {
176         for (Destination destination : _destinations.values()) {
177             destination.close(force);
178         }
179     }
180 
181     public synchronized boolean unregisterMessageListener(
182         String destinationName, MessageListener messageListener) {
183 
184         Destination destination = _destinations.get(destinationName);
185 
186         if (destination == null) {
187             return false;
188         }
189 
190         boolean unregistered = destination.unregister(messageListener);
191 
192         if (unregistered) {
193             fireMessageListenerUnregisteredEvent(destination, messageListener);
194         }
195 
196         return unregistered;
197     }
198 
199     protected void fireDestinationAddedEvent(Destination destination) {
200         for (DestinationEventListener listener : _destinationEventListeners) {
201             listener.destinationAdded(destination);
202         }
203     }
204 
205     protected void fireDestinationRemovedEvent(Destination destination) {
206         for (DestinationEventListener listener : _destinationEventListeners) {
207             listener.destinationRemoved(destination);
208         }
209     }
210 
211     protected void fireMessageListenerRegisteredEvent(
212         Destination destination, MessageListener messageListener) {
213 
214         for (DestinationEventListener destinationEventListener :
215                 _destinationEventListeners) {
216 
217             destinationEventListener.messageListenerRegistered(
218                 destination.getName(), messageListener);
219         }
220     }
221 
222     protected void fireMessageListenerUnregisteredEvent(
223         Destination destination, MessageListener messageListener) {
224 
225         for (DestinationEventListener destinationEventListener :
226                 _destinationEventListeners) {
227 
228             destinationEventListener.messageListenerUnregistered(
229                 destination.getName(), messageListener);
230         }
231     }
232 
233     private static Log _log = LogFactoryUtil.getLog(DefaultMessageBus.class);
234 
235     private Set<DestinationEventListener> _destinationEventListeners =
236         new ConcurrentHashSet<DestinationEventListener>();
237     private Map<String, Destination> _destinations =
238         new HashMap<String, Destination>();
239 
240 }